U.S. Pat. No. 4,096,711 issued Jun. 27, 1978 to G.A. Carlson, et al. teaches a dual flex plate drive for use between a torque converter and a transmission to reduce torsional vibration levels and to compensate for misalignment. In that drive a plurality of flat annular discs of steel material are stacked together to form a flexible drive plate assembly at each end of a centrally disposed drive tube. A single one of these drive plate assemblies has been used with some success between a diesel engine flywheel and an electric generator set's input drive shaft to reduce the amplitude of linear vibrations of the generator set. However, a single assembly is too stiff radially and has a limited ability to accommodate misalignment between the driving and driven members and, accordingly, drive plate assemblies have been used in tandem to increase the maximum capacity for misalignment. The tandem solution is more costly because it has more piece parts, and it requires considerable axial space.
There are a number of other coupling designs which provide various amounts of flexibility and/or stiffness in the radial and axial directions, and some resistance to bending with the imposition of torsional loads under a relatively limited range of misalignment between the input and output members thereof. Representative of the art in this area are the following U.S. Pat. Nos.:
2,281,898 issued May 5, 1942 to O.M. Whitten. PA1 3,283,536 issued Nov. 8, 1966 to W. Fisher. PA1 3,371,549 issued Mar. 5, 1968 to E. Schrempp. PA1 3,808,837 issued May 7, 1974 to N.J. Anderson et al PA1 3,955,377 issued May 11, 1976 to W.H. Bendall.
For the most part, these couplings are too costly and/or are more difficult to manufacture or assemble in use. They also exhibit deficiencies in continuously transmitting the desired high levels of torque under preselected ranges of radial, axial and bending flexibility without excessive stress levels.
Therefore, what is desired is an economical flexible coupling having a simple and rugged construction, and that requires a relatively limited amount of axial and radial space. For example, it should preferably be all-metallic to eliminate the problems associated with deterioration of elastomeric or rubber elements under the hot and oily environments so typically encountered. Moreover, the coupling must be sufficiently flexible to accept various types of misalignment between the axes of the driving and driven members while simultaneously having the capability to transmit the desired amount of torque, and to have relatively wide ranges of radial and bending flexibility while controlling the resonances of the drive line such that linear vibration of any portion of the total package is reduced to an acceptable level.
The present invention is directed to overcoming one or more of the problems as set forth above.